Why does my (hardwired) Gen 4 Tablo (when viewed by my my Roku Ultra app) not able to tune in on certain channels , but I can watch those channels via wifi on my Amazon Fire Tablets , without issues.
If you did the set up on the Roku, it’s possibly due to the Roku Tablo app’s jumbling the channel line-up.
Use your smartphone / tablet app to redo the channel scan & lineup selection. Before you start, you’ll need to first redo selecting the channel line-up, purposely clearing all channels except for one streaming. Then re-scan, and select your preferred lineup.
Power reset your Roku before trying to use its Tablo app. After it resets, the Tablo app should acquire the new, correct lineup when it opens and those inconsistencies should be gone.